Analysis of the repetitively pulsed dual-beam thermo-optical absorption spectrometer

Abstract

An analysis is presented for the repetitively pulsed dual‐beam thermo‐optical absorption spectrometer, which has been used recently to determine the absorption strengths of several organic liquids in the visible spectral region covered by the cw tunable dye laser. The model succeeds in describing the development of the thermal lens on a pulse‐by‐pulse basis. The equations derived are then used to optimize the spectrometer design with respect to the parameters which are under the control of the experimenter. It is further demonstrated how one identifies the region of linear operation of the spectrometer. Finally, it is shown how the relative absorptivities of compounds may be determined.